2. Solar thermal energy​Solar thermal energy (STE) is an innovative technology for harnessing solar energy for thermal energy. Solar thermal collectors are classified by the United States Energy Information Administration as low-, medium-, or high-temperature collectors. Low-temperature collectors are flat plates generally used to heat swimming pools. Medium-temperature collectors are also usually flat plates but are used for heating water or air for residential and commercial use.Read “Solar thermal energy” on English WikipediaRead “太陽熱発電” on Japanese WikipediaRead “Solar thermal energy” on DBpedia